The manufacture of various polymers frequently involves a final drying step in order to remove water and other volatile components utilized in the polymerization. For example, the drying process can include drying a wet polymer powder using large industrial dryers (such as fluidized bed driers), nitrogen delivery systems, and scrubber systems to control the unwanted escape of volatile components into the environment. While such dryers are typically effective at reducing the moisture and volatile organic content of a variety of polymer powders, processes using them are relatively slow and costly. A further drawback to drying polymer powders arises as the drying process progresses, where, when the moisture level present in a polymer powder falls below a critical moisture content, the drying rate can be limited by the rates of liquid diffusion and capillary transport in the powder particles. Thus, the last stages in the drying of a polymer powder can be difficult and can require long drying times, for example, on the time scale of hours to tens of hours.
A process that more efficiently dries a polymer powder is therefore desirable. It would further be beneficial if the drying process could further produce one or both of polycarbonate pellets and extruded polycarbonate compositions comprising one or more additives.